What energy source do molecular motors use?

Molecular motors, such as kinesin and dynein, primarily utilize ATP as their energy source. The hydrolysis of ATP to ADP and inorganic phosphate releases energy, which is harnessed by these motors to facilitate movement along cytoskeletal components, like microtubules and actin filaments. This process is essential for various cellular activities, including intracellular transport, muscle contraction, and cell division.

ATP is critical because it provides the necessary energy currency for numerous cellular processes, and its hydrolysis leads to conformational changes in molecular motors that enable them to "walk" along their tracks within the cell. In contrast, while GTP is involved in other molecular processes such as protein synthesis and signaling pathways, it is not the main energy source for molecular motors. Glucose is a broader source of energy for cellular metabolism but is not directly utilized by molecular motors. ADP, on the other hand, is a product of ATP hydrolysis and does not serve as an energy source for these motors.